FAQ Section

RJ45 modular plug design

[Q] Why are there different designs of RJ45 modular plugs?
Does the design effect performance?

[A] RJ45 modular plugs are made in several different designs, and
there are a few major characteristics that can be discussed:

Pin
Capture Design - On most RJ45 plugs, the end of the plug
has a flat surface that the individual wires are pressed into,
until they "dead-end". The person inserting the
wires holds a bit of pressure on the pairs until the crimper
is used to press the copper forks downward into the wires,
making a solid connection and helping secure the CAT 5
Cable in the plug. There are other plugs designed with
holes in the end, requiring that the operator push additional
length of wire through the plug, then a specialized crimper
will utilized a built-in cutting blade to slice the excess
wire even with the end of the modular plug that inserts to
the jack. In order to gain the extra material needed for this
operation, you must strip more of the outer jacket, thus using
more material to make each cable. The amount is slight, but
it does need to be compensated for in order to ensure that
your finished cable length is exact.

Plug
Length - The overall length of the plug is not a factor
in how the RJ45 plug will fit into the jack, so some plug
designers will make the plug with a slightly larger total
length. This is usually to allow for more distance between
the insertion point of the cable where the crimper will lock
the plug onto the jacket, down to the very end of the plug
where the copper forks press into the actual wires and form
a connection.

Location and number of crimp points - Most RJ45
plugs have a single crimp point slightly forward of the
insertion end of the plug. That crimp point, along with the
actual insertion into the wires is what secures the cable
into the plug. The are some specialized designs on the market
that have additional crimp points that are supposed to lock
the cable more securely into the plug. This is not a big factor
to worry about, as most plug designs will hold a cable very
securely using just the standard two crimping locations common
to modern plug design. The pulling strength required to remove
the cable from the jacket will well exceed the recommended
pulling tension of the wire specified by the cable maker.

The
design of the plug does not directly relate to the performance
you can expect from the cable. Any of the plug designs described
above can give poor performance if it is crimped improperly.
If crimped to specifications, all plugs designs should deliver
the same overall performance.